MEMS Viscosity sensors are widely used in different applications nowadays. MEMS sensors are created by making them small in size almost penny-like sized. With low power consumption, cheap costs of production, and mass production of the devices. These sensors are able to measure viscosity through three different characteristics, the frequency, amplitude and the quality factor. Each of these describes the fluids viscosity, by using a vibrational type viscometer. The sensor has been proven to work in conductive fluids after a post process fabrication of a protective layer of Parylene C. The sensors performance has been altered due to a thicker membrane, but still operates as expected. The MEMS viscosity sensor has been tested in various glycerol water mixtures to simulate conductive fluids with varying viscosity. The tests had positive outcomes, and the sensors performance was not altered, they worked as predicted. Different tests were accomplished to make sure the sensors performance remained close to normal operations after adding the protective layer of Parylene C. Four distinct oils were chosen to accomplish this variation test. Oil was chosen rather than a conductive liquid in order to prevent the sensor from damaging itself, and having to repackage another sensor and running all the previous tests. With these tests the sensor proved that adding a thin layer of Parylene C does not alter the sensors performance, but it does tend to change some of the theoretical calculations because there are various factors involving the addition of a protective layer post fabrication. In this case a layer of 0.5 micro meters of Parylene C is thick enough to protect against conductive fluid. Overall the addition of the protective layer shielded the sensor from conductive fluids and prevented the electrical currents to expand through the conductive fluid.
Library of Congress Subject Headings
Microelectromechanical systems--Design and construction; Viscosity--Measurement
Department, Program, or Center
Microelectronic Engineering (KGCOE)
Gan Chau, Luis, "A MEMS viscosity sensor for conductive fluids" (2012). Thesis. Rochester Institute of Technology. Accessed from
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